Concrete Expansion Joint Forming Device

ABSTRACT

In one aspect of the present invention there is provided an expansion joint strip support module  12  comprising an expansion joint strip locating portion  24  adapted to locate an expansion joint strip  20  and one or more support means  26  and  28  integral with and arranged to support the expansion joint strip locating portion. 
     In a further aspect of the present invention there is provided an expansion joint crack forming device comprising: an elongate base strip  14  being adapted to extend along a proposed expansion joint; and a crack forming projection  84  connected to the base strip  14  and designed to form a cavity in a concrete slab which is to be formed on top of the base strip  14 , the crack forming projection  84  being positioned to promote cracking of the concrete slab along the proposed expansion joint.

PRIORITY CLAIM

This application is a national stage application of InternationalApplication No. PCT/AU2005//001218, filed on Aug. 12, 2005 which claimspriority to, and the benefit of, Australian Provisional Application No.2004904549, filed Aug. 13, 2004, the entire content of which is herebyincorporated by reference.

FIELD OF THE INVENTION

The present invention relates to concrete expansion joints. Moreparticularly, the present invention relates to a support assembly for anexpansion joint strip and a method for installing an expansion jointstrip in a concrete slab.

BACKGROUND OF THE INVENTION

Concrete floors and paving typically comprise a number of concreteslabs. The concrete slabs are typically designed for movement relativeto each other to avoid formation of cracks in the floor or paving whichwould otherwise form with thermal expansion and contraction of theconcrete slab and movement of supporting foundations. Concrete slabs aretypically separated from each other by concrete expansion joints whichusually comprise a compressible expansion joint strip. Compressibleexpansion joint strips fill the gaps between concrete slabs whileallowing movement toward and away from each other.

Devices for positioning an expansion joint strip and formation of acorresponding expansion joint between concrete slabs are disclosed inU.S. Pat. No. 6,598,364 B1 and Danley Construction Products Pty Ltd andConnolly Key Joint Pty Ltd websites www.danley.com.au andwww.connollykeyjoint.com respectively. The corresponding expansion jointforming devices are typically cumbersome and time consuming to erect.

SUMMARY OF THE INVENTION

According to one aspect of the present invention there is provided asupport assembly for an expansion joint strip, said assembly comprising:an elongate base strip including at least two laterally spaced locatingwalls; a plurality of discrete support modules each being detachablyconnected to the locating walls at longitudinally spaced positions alongthe base strip; and means for adjusting the height of the expansionjoint strip relative to at least one of the support modules.

Preferably the support assembly also comprises an expansion joint stripcover adapted to support the expansion join strip and being arranged tobe supported by one or more of the support modules. More preferably eachof the modules includes a U-shaped channel configured to cradle theexpansion joint strip cover.

Preferably the height adjustment means includes a pin being designed tolocate at one of a plurality of different height positions relative tothe corresponding support module. More preferably the pin is received inone of a plurality of locating holes in the support module, the stripcover being designed to rest on the pin to support the expansion jointstrip at the required height. Even more preferably the pin is enlargedat one end for press-fit engagement with said one of the locating holes.

Preferably the locating walls are each in the form of stiffening ribsdesigned to strengthen the base strip.

Preferably the support modules include a pair of spaced support legseach being perforated to promote the flow of concrete and encasing ofsaid modules.

Preferably said locating walls include a pair of outer locating wallsand a central locating wall. More preferably the base strip includes agroove or slot underlying the central wall and designed to allow lateralmovement of the strip.

Preferably the support assembly also comprises another base strip joinedto said base strip at an expansion joint juncture.

According to another aspect of the invention there is provided a methodof installing an expansion joint strip in a concrete slab, said methodcomprising the steps of: providing an elongate base strip having atleast two laterally spaced locating walls; providing a plurality ofdiscrete support modules; fitting two or more of the support modules tothe locating walls of the base strip at spaced longitudinal positionsalong the base strip; placing the expansion joint strip upon one or moreof the modules and adjusting the height of said strip relative to atleast one of said modules; and pouring concrete to at least partly burythe base strip, the support modules and the expansion joint strip.

Additional features and advantages of the present invention aredescribed in, and will be apparent from, the following DetailedDescription of the Invention and the figures.

BRIEF DESCRIPTION OF THE FIGURES

A preferred embodiment of the present invention will now be described,by way of example only, with reference to the following figures inwhich:

FIG. 1 is a partially exploded perspective view of one example of anexpansion joint strip support assembly of the present invention.

FIG. 2 is an end elevational view of the expansion joint strip supportassembly of FIG. 1 in its assembled condition.

FIG. 3 a is a perspective view of a base strip from the assembly of FIG.1.

FIG. 3 b is an end elevational view of the base strip of FIG. 3 a.

FIG. 4 is an end elevational view of the base strip of FIG. 3 a used todirectly support a compressible expansion joint strip.

FIG. 5 is a perspective view of an alternative example of an expansionjoint strip support assembly of the present invention.

FIG. 6 a is a perspective view of an expansion joint strip supportassembly similar to that of FIG. 5.

FIG. 6 b is an end elevational view of an alternative strip cover tothat of FIG. 6 a.

FIG. 7 is an end elevational view of the expansion joint strip supportassembly of FIGS. 5 and 6 but without a concrete slab locating rod.

FIG. 8 is an end elevational view similar to that of FIG. 7 except thatit includes the concrete slab locating rod of FIGS. 5 and 6.

FIG. 9 is an end elevational view of the expansion joint strip supportassembly of FIG. 1 attached to another expansion joint strip supportassembly.

FIG. 10 is a perspective view of an expansion joint strip supportassembly similar to that of FIG. 9 attached via an alternativeattachment bracket.

FIG. 11 is a perspective view of another alternative example of anexpansion joint strip support module of the present invention.

FIG. 12 is a perspective view of 2 base strips of FIG. 1 attached end toend.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 to 3 b show an expansion joint strip support assembly of thepresent invention in the form of support assembly 10. The supportassembly 10 comprises an expansion joint strip support module in theform of support module 12, a base strip 14 and an expansion joint stripcover in the form of strip cover 16. The support module 12 attaches tothe base strip 14 as shown in FIGS. 1 and 2 which is described in detailbelow. FIGS. 1 and 3 a show only a portion of the entire length of thebase strip 14. The base strip 14 ranges from about 4 metres to about 6metres in length. Support modules 12 are positioned along the length ofthe base strip 14 and attached to the base strip so that they arelongitudinally spaced apart by about 400 mm. With support modules 12spaced in this manner along the base strip 14 they are each able tosupport, as described below, a portion of an expansion strip in the formof a compressible expansion joint strip 20. The expansion joint strip 20is typically a tar based compressible expansion strip. With theexpansion joint strip 20 supported as shown in FIG. 2 it is supportedfor separation of concrete slabs 250 and 252 which are subsequentlypoured on either side of the compressible expansion joint strip 20. Thesupport module 12 is suitable for concrete slabs of any thickness.

The support assembly 10 shown in FIG. 2 is assembled first by placingthe base strip 14 on the floor or ground which is to support theconcrete slabs 250 and 252. The floor may, for example, be elevated. Thebase strip 14 is positioned on the floor or ground so that it's alignedwith the space between the proposed concrete slabs 250 and 252. Otherbase strips 14 are also positioned on the floor or ground both parallelwith and normally to other base strips to correspond with thepredetermined arrangement of expansion joints. If the base strips arepositioned on the ground they are usually attached via pegs, forexample, pegs 15 (see FIGS. 1 and 2) as shown in FIG. 2. Plastic sheet,(not shown) are then laid over the base strips and slits are cut in theplastic to enable locating walls of the base strip which are describedbelow to pass up through the plastic sheets. The plastic sheets functionto seal the floor or ground to prevent moisture seeping upwardly intothe concrete slab. Once all of the base strips 14 relating to a specificsurface area have been appropriately positioned, reinforcing mesh (notshown) is then positioned appropriately on top of the base strips 14.For some applications the mesh is cut above the locating walls so thatit is not exposed after concrete is poured but is entirely embedded inthe concrete. The support modules 12 are then positioned above the basestrip 14 to which they are to be attached so that they attach to thebase strip 14 as shown in FIGS. 1 and 2 by passage through holes of themesh (not shown). The support modules 12 also function to attach theplastic sheets to the base strips 14.

The position of an upper surface 136 of the compressible expansion jointstrip 20 relative to the upper surface 104 of the base strip 14 isadjusted by passing a locating pin 138 through opposed holes 38 and 40of the U-shaped channel 24 as shown in FIG. 2. The upper surface 136 ofthe compressible expansion joint strip 20 can be used as a guide forforming an upper surface of the concrete slabs 250 and 252. The means ofadjustment involving the opposed holes 38 and 40 and the locating pin138 can therefore be used, for example, to correct for any unwantedvariation in the floor or ground height or alternatively to produce asloping upper surface 136 to allow for drainage.

Features of the support module 12, base strip 14 and strip cover 16 willbe described in more detail before providing a more detailed descriptionof assembly of the support assembly 10. The support assembly 10comprises an expansion joint strip locating portion in the form of aU-shaped channel 24 and support legs in the form of planar legs 26 and28. The U-shaped channel 24 comprises opposed side walls 32 and 34 andan adjoining base 36. The U-shaped channel 24 also includes adjustmentmeans in the form of opposed holes 38 and 40 formed in respective sidewalls 32 and 34.

The planar leg 26 comprises 3 adjoining planar leg portions in the formof adjoining leg portions 46, 48 and 50. The adjoining planar leg 28similarly comprises 3 adjoining planar leg portions in the form ofadjoining leg portions 50 to 54 and 56. Although not shown in FIG. 1,planar leg portions 26 and 28 are perforated as described below inrelation to support module 142 (see FIGS. 5 and 6 a) for flow ofconcrete or other cementitious material into the space underneath theleg portions 26 and 28. In the support module 12 the adjoining legportions 50 and 56 are integrally formed with the base 36 of theU-shaped channel 24. The other adjoining leg portions of the supportmodule 12 are also integrally formed with the adjoining leg portions 50and 56. The side walls 32 and 34 of the U-shaped channel 24 are alsointegrally formed with the base 36 and the adjoining leg portions 50 and56. In one alternative embodiment of the support module 12 the base 36is V-shaped so that its longitudinal axis is positioned below its upperlongitudinal edges. In this alternative embodiment a corresponding stripcover is identical to strip cover 16 except that its base is alsov-shaped. The support module 12 is manufactured by cutting acorresponding extrusion into 80 mm lengths. It will be appreciated bypersons skilled in the relevant art that the support module 12 can bemanufactured by other means and could for example be injection mouldedor formed from separate components corresponding to the adjoining legportions, base 36 and side walls 32 and 34.

The adjoining leg portions 46 and 52 comprise attachment means forattachment to the base strip 14. The attachment means of the adjoiningleg portions 46 and 52 is in the form of respective locating slots 60and 62. Each of the locating slots 60 and 62 comprises locating slotwalls 64 and 66, and 68 and 70 respectively. The walls 64, 66, 68 and 70are resiliently deformable for attachment to the base strip 14. Formedon the inner surface of walls 64 and 70 are engaging surfaces in theform of barbs 74. The barbs 74 are designed for engagement withcorresponding engaging features of the base strip 14 which are describedbelow.

The base strip 14 is also extruded and includes 2 outer locating wallsin the form of outer locating walls 80 and 82 and a central locatingwall in the form of central locating wall 84. The outer and centrallocating walls are the attachment means of the base strip 14 forattachment to a support module such as support module 12. The centrallocating wall may also function to elevate the reinforcing mesh whichreduces or in some cases may replace the need for reinforcing meshsupport cradles.

Outer locating walls 80 and 82 include on their outer surfaces 86 and 88respectively engaging surfaces corresponding to the engaging surfaces ofthe locating slots 60 and 62 in the form of barbs 90. As can be seenfrom FIGS. 1 and 2 the barbs 74 and 90 are designed to slide over eachother as the outer locating walls 80 and 82 are forced into thecorresponding respective locating slots 60 and 62. Insertion of thelocating walls into the slots results in the corresponding locating slotwalls resiliently separating and then resiliently compressing againstthe locating walls when the respective barbs 74 and 90 are appropriatelyengaged in the position shown in FIG. 2. Relative orientation of thebarbs 74 and 90 means that withdrawal of the outer locating walls 80 and82 from the corresponding respective locating slots 60 and 62 isresisted by engagement of the respective barbs as shown in FIG. 2.

The height of the outer locating walls 80 and 82 and the depth of thecorresponding respective locating slots 60 and 62 is such that thelocating walls are fully received within the corresponding locatingslots before free ends 100 and 102 of the planar legs 26 and 28 (seeFIG. 2) contact an upper surface 104 of the base strip 14.

The base strip 14 includes outer regions in the form of recessed regions110 and 112. The recessed regions 110 and 112 have correspondingrespective recessed surfaces 114 and 116 which are offset relative tothe upper surface 104 of the base strip 14. The base strip 14 alsoincludes recess strips in the form of recess strips 120 and 122 whichare formed in an underneath side of the base strip 14. Finally, the basestrip 14 includes a groove in the form of a V-shaped groove 106 (seeFIGS. 1 and 2) which is also formed in the underneath side of the basestrip 14 and positioned directly beneath the central locating wall 84.Referring to FIG. 3 b, the V-shaped groove 106 in an alternativeembodiment coincides with a deflection slot 108. The V-shaped groove 106and optional deflection slot 108 enable sides of the base strip 14 todeflect relative to each other in a plane which is substantially normalto a longitudinal axis of the base strip 14. This ability to deflectenables the base strip 14 to accommodate movement in the ground or floorwithout affecting its integrity. The deflection slot 108 may extend theentire depth of the central locating wall 84.

FIG. 4 shows an alternative use of the base strip 14. In thisalternative use the base strip 14 directly supports an assembledcompressible expansion joint strip 20 and corresponding strip cover 16by attachment of the expansion joint strip and strip cover directly tothe central locating wall 84. In this alternative use of the base strip14, the base strip 14 functions as an expansion joint strip supportmodule. The central locating wall 84 functions as an expansion jointstrip locating projection of that module while the support means of theexpansion joint strip support module comprises the plates 85 and 87which the central locating wall 84 is integrally formed with and whichare positioned on either side of the central locating wall. Thisalternative use of the base strip 14 is used to form reduced depthconcrete slabs consisting of concrete slabs 320 and 322 positionedeither side of an expansion joint strip 324.

The alternative use of the base strip 14 shown in FIG. 4 can also beused to top an existing concrete slab. The base strip 14 is positionedon top of an existing concrete slab 330 and attached to that slab viascrews 332. Pouring concrete on top of the base strip 14 then results information of the slabs 320 and 322 and the corresponding expansion joint324. Expansion joints similar to expansion joint 324 positioned on topof the existing concrete slab 330 can be used, as described above, tolevel concrete slabs formed on top of the existing slab 330. Thisprocess can also be used to improve the finished surface of a concreteslab.

The alternative use of the base strip 14 shown in FIG. 4 can also beused to form full depth expansion joints by using strip cover andcompressible expansion joint strip assemblies described below inrelation to the support assembly 140. The strip cover 16 comprises aU-shaped channel 130 having opposed side walls 132 and an adjoining base134. The strip cover 130 is designed to cover the compressible expansionjoint strip 20 as shown in FIGS. 1 and 2. With the strip cover 130covering the compressible expansion joint strip 20 it can be placed intothe U-shaped channel 24 for support by the support module 12. Althoughthe strip cover 16 is designed to increase the rigidity of thecompressible expansion joint strip 20 which, as described below, makesit suitable for directly inserting an assembled strip cover andexpansion joint strip into wet concrete, the strip cover 16 is alsoflexible in a plane which is aligned with the adjoining base 134. Thestrip cover 16 can therefore be used for forming non linear expansionjoints.

An alternative expansion joint strip support assembly in the form ofsupport assembly 140 is shown in FIGS. 5 to 8. The support assembly 140includes a support module 142, base strip 144 and strip cover 146. Thesupport module 142 differs from the support module 12 and is describedin detail below. The base strip 144 is identical to the base strip 14and its features are referenced using the reference numerals of basestrip 14. The strip cover 146 is the same as the strip cover 16 exceptthat it is deeper for receipt of a deeper compressible expansion jointstrip 148 (see FIGS. 6 a, 7 and 8). The strip cover 146 may also includeholes (not shown) for receipt of locating rods 150, as described below.

The support assembly 140 also includes a concrete slab locating rod 150(see FIGS. 5, 6 a and 8). The locating rod 150 also forms part of thesupport assembly 10 and the description relating to the locating rod 150in relation to its use with the support assembly 140 also applies to useof the locating rod 150 with the support assembly 10.

The support module 142 is formed as described above in relation to thesupport module 12 by cutting 80 mm lengths from a correspondingly shapedextrusion. The support module 12 includes a planar leg 160 which isessentially identical to the planar leg 26 of the support module 12. Theplanar leg 160 includes intersecting leg portions 162, 164 and 166. Theintersecting leg portion 162 includes a locating slot 170 formed betweenlocating slot walls 172 and 174. Barbs 176 are formed on an innersurface of the locating slot wall 172 as described above in relation tothe support module 12.

The support module 142 includes an expansion joint strip locatingportion in the form of U-shaped channel 180. The U-shaped channel 180includes side walls 182 and 184 and an adjoining base 186. The side wall182 extends from the base 186 upwardly beyond the intersecting legportion 166. An upper end of the extension of the side wall 182 is inthe form of a strip cover locating projection 190.

The support module 142 also includes attachment means in the form of alocating slot 192 formed between a locating slot wall 194 and an outersurface of the side wall 182 and its corresponding upward extension.Formed on the inner surface of the locating slot 192 are engagingsurfaces in the form of barbs 196. The locating slot 192 is designed forengagement with the central locating wall 84 of the base strip 144 asdescribed in relation to the locating slot 170.

The side wall 182 and its corresponding upward extension which connectsto the intersecting leg portion 166, as well as the base 186 of theU-shaped channel 180 also functions as a second support leg of thesupport module 142.

In addition to being a different height than the strip cover 16 of thesupport assembly 10, the strip cover 146 includes an axial flange 200.The axial flange 200 attaches to an outer surface of a side wall 202 ofthe strip cover 146. The axial flange 200 provides a module locatingslot 204 for receipt of the strip cover locating projection 190 of thesupport module 142. The axial flange 200 prevents the strip cover 146and corresponding compressible expansion joint strip 148 from tiltingaway from the strip cover locating projection 190. The axial flange 200also stiffens the strip cover 146 to prevent distortion, particularly ina plane which is parallel with the base 186 of the U-shaped channel 180.The axial flange 200 also increases torsional stiffness of the stripcover 146 about its longitudinal axis.

An alternative strip cover 147 is shown in FIG. 6 b. This alternativestrip cover is designed to locate an expansion joint strip in the formof compressible expansion joint strip 149 which is typically known topeople skilled in the relevant art as a “metal cracker strip”.Compressible expansion joint strip 149 includes a metal strip 152 and acompressible strip 154.

The strip cover 16 of the support assembly 10 and the strip covers 146and 147 of the support assembly 140 can be used independently of thecorresponding support modules 12 and 142 and base strips 14 and 144 toform an expansion joint. The strip covers 16, 146 and 147 sufficientlyincrease the rigidity of the corresponding respective compressibleexpansion joint strips 20, and 148 and 149 to enable the assembled stripcovers and compressible expansion joint strips to be inserted into wetconcrete. Advantages provided by remaining components of the supportassemblies 10 and 140 as described throughout the specification may beconsidered unnecessary for a particular application. If so, thisalternative use of the assembled strip covers and compressible expansionjoint strips enables expansion joints to be formed more easily and costeffectively.

The locating rod 150 includes a locating sleeve 206 and a correspondingrod 208. As can be seen from FIG. 8 an end 210 of the locating rod 208is positioned close to a blind end 212 of the locating sleeve 206.Referring to FIGS. 5 and 6 a the locating sleeve 206 has lower and upperwalls 214 and 216. The distance between inner surfaces of these lowerand upper walls is less than the separation of internal surfaces of thewalls which join the lower and upper walls 214 and 216. Referring toFIG. 8, the locating sleeve 206 limits upward and downward movement ofthe round locating rod 208 but allows some movement in a lateraldirection.

The locating sleeve 206 includes a locating rod locator 220 forattachment of the locating rod 206 to the base strip 144. The locatingrod locator 220 is integrally formed with the locating sleeve 206 andincludes at an end remote from the locating sleeve a locating slot 222which is described in the relation to the locating slot 170. Thelocating slot 222 is designed for removable attachment to the locatingslot wall 172 as described above in relation to the location slot 170and locating slot wall 172.

For some applications the strip cover 146 does not include holes in itswalls but is marked for formation of holes through its walls and alsothrough the compressible expansion joint strip 148 located between thestrip cover side walls. These holes (not shown) are designed for passagethrough the strip cover 146 and corresponding compressible expansionjoint strip 148 of the locating rod 150. The holes in the strip coverand compressible expansion joint strip are usually more easily formedprior to assembly of the strip cover and support module 142 using anappropriate tool.

The support module 142 is attached to the base strip 144 as describedabove in relation to the support assembly 10. The strip cover 146 oralternative strip cover 147 and associated respective compressibleexpansion joint strip 148 or 149 is then fitted into the U-shapedchannel 180 so that the strip cover locating projection 190 slidesupwardly through the module locating slot 204. With the strip cover 146and support module 142 assembled as shown in FIGS. 5 to 8 walls of thestrip cover 16 are clamped together via a clip 340 as shown in FIG. 6 a.The clip 340 prevents walls of the strip cover 146 separating ifconcrete being poured on one side of an expansion joint flows on top ofthe expansion joint strip. A similar clip (not shown) can be designedfor use with the alternative strip cover 147.

The locating rod 150 is inserted through holes in the strip cover andexpansion joint strip 148 and then attached to the base strip 144 asshown in FIGS. 5, 6 a and 8. To prevent removal of the compressibleexpansion joint strip 148 it can be screwed to the corresponding stripcover 146 and the strip cover locating projection 190 by screws 260 (seeFIG. 8).

Referring to FIGS. 5 and 6 a the intersecting leg portions 164 and 166have perforations in the form of round holes 230 and 232 and square andrectangular holes 234 and 236. These holes ensure that concrete or othercementitious material flows into the space underneath the intersectingleg portions 164 and 166 as it is poured onto the base strip 144 andagainst side wall 202 of the cover strip 146 to form slab 240 (see FIGS.7 and 8) which abuts the side wall 202.

After concrete is poured on both sides of the compressible expansionjoint strip 148 it sets around the locating sleeve 206 and locating rod208. After the concrete slabs 240 and 242 set they will move relative toeach other in response to changes in temperature and movement of thesupporting floor or ground. Movement of the concrete slabs normally ofthe compressible expansion joint strip 148 is accommodated bycompression and expansion of that strip and axial movement of thelocating rod 208 within the locating sleeve 206. Movement of the slabs240 and 242 in a direction aligned with a longitudinal axis of the basestrip 144 lies is accommodated by lateral movement of the locating rod208 within the locating sleeve 206.

As can be seen in FIGS. 7 and 8 the compressible expansion joint strip148 extends the entire depth of concrete slabs 240 and 242. This is incontrast to the compressible expansion joint strip 20 of the supportassembly 10 (see FIG. 2) which only extends partway into the depth ofconcrete slabs 250 and 252. The concrete slabs 250 and 252 join beneaththe base 36 of the U-shaped channel 24 and above the central locatingwall 84. Contrastingly, the concrete slabs 240 and 242 of the supportassembly 140 are completely separated by the corresponding compressibleexpansion joint strip 148. The central locating wall 84 of the supportassembly 10 (see FIG. 2) functions as a crack propagator to facilitateformation of a crack above the central locating wall 84 in the eventthat slabs 250 and 252 move. The central locating wall 84 thereforefunctions to limit the likelihood of cracks occurring within slabs 250and 252.

Termites typically pass from the ground into a building via its walls bypassing upwardly through expansion joints of corresponding concreteslabs. The base strips 14 and 144 of FIGS. 1 and 5 prevent this fromoccurring by sealing the expansion joint from the correspondingsupporting floor or ground.

Support assemblies 10 and 140 can be joined to corresponding supportassemblies which, for example, extend normally of those supportassemblies for intersection of corresponding expansion joints. Oneexample of intersecting support assemblies is shown in FIG. 9 inrelation to support assembly 10. A support assembly ie 10′ appears onthe left of the support assembly 10. A compressible expansion jointstrip 20′ of the support assembly 10′ extends normally of thecompressible expansion joint strip 20 of the support assembly 10.Referring to FIGS. 1 and 9, material from an underneath surface of endregion 270 of the base strip 14′ is removed to enable the end region 270to sit on top of recessed surface 114 of the base strip 14. Material isremoved or checked out from the end region 270 so that an end 276 of thebase strip 14′ either abuts or is positioned close to an abuttingsurface 278 of the base strip 14.

With the support assemblies 10 and 10′ positioned as shown in FIG. 9 thecorresponding base strips 14 and 14′ are attached relative to each otherusing a base strip locator in the form of base strip locator 280. Thebase strip locator 280 includes a locating slot 282 and another locatorin the form of base strip locating lug 284. The locating slot 282 hasthe features described in relation to locating slots 60 and 62 and isdesigned for attachment to the outer locating wall 80 as described abovein relation to the locating slot 60 and outer locating wall 80. Thelocating lug 284 is designed to sit above the upper surface 104 of thebase strip 14′ and locate the end region 270 of the base strip 14′between the locating lug 284 and the recessed surface 114 of the basestrip 14. The strip covers 16 and 16′ of the respective supportassemblies 10 and 10′ are attached via an angled bracket 290.

The base strip locator 280 may, for example, in place of the base striplocating lug 284 include another locating slot (not shown) identical tothe locating slot 282 but designed for attachment to outer locatingwalls 80′ or 82′ of the base strip 14′.

FIG. 10 corresponds to FIG. 9 and includes angled brackets 350 and 352in place of the angled bracket 290. FIG. 10 also shows that part of theouter locating wall 80 of the base strip 14 has been removed to providean unobstructed region adjacent the central locating wall 84′ of thebase strip 14′ which extends through to the central locating wall 84 ofthe base strip 14.

FIG. 11 shows a support module 300 which is effectively identical to thesupport modules 12 and 12′ except that it includes intersecting U-shapedchannels 302 and 304. The support module 300 therefore providesalternative means to that described in relation to FIGS. 9 and 10 tojoin compressible expansion joint strips that extend normally of eachother. Intersecting base strips are joined as described above inrelation to base strips 14 and 14′ of FIGS. 9 and 10. The compressibleexpansion joint strip (not shown) which is received within the U-shapedchannel 304 would normally extend continuously through the intersectionwith the U-shaped channel 302 and compressible expansion joint strips ofchannel 302 would normally abut the continuous expansion joint strip.

Support assemblies 10 and 140 can also be joined to correspondingsupport assemblies which are aligned with those support assemblies forend to end connection of corresponding expansion joints. End to endconnection of base strips 14 is shown in FIG. 12. This end to endconnection includes an end to end base strip coupling 360. The basestrip coupling 360 includes barbs 362 which are designed for removableattachment to locating walls 80, 82 and 84 of the base strip 14 asdescribed above in relation to the support assemblies 10 and 140.

Support assemblies 10 and 140 of these embodiments of the presentinvention provide a number of advantages:

(a) quick and easy assembly involving placement of freestandingintegrally formed support modules 12 and 142.

(b) sealing of an expansion joint from underneath abutting concreteslabs to prevent termites or moisture passing upwardly through theexpansion joint; and

(c) quick, easy and discrete adjustment of upper surfaces of thecompressible expansion joint strips 20 and 148.

All publications mentioned in this specification are herein incorporatedby reference. Any discussion of documents, acts, materials, devices,articles or the like which has been included in the presentspecification is solely for the purpose of providing a context for thepresent invention. It is not to be taken as an admission that any or allof these matters form part of the prior art base or were common generalknowledge in the field relevant to the present invention as it existedanywhere before the priority date of each claim of this application.

It will be appreciated by persons skilled in the art that numerousvariations and/or modifications may be made to the invention as shown inthe specific embodiments without departing from the spirit or scope ofthe invention as broadly described. For example, an inverted T-shapedsupport leg may replace the planar legs 26 and 28 of the supportassembly 10, in which case, the base strip 14 would not include thecentral locating wall 84. This alternative support leg could, forexample, attach to the adjoining base 36 of the U-shaped channel 24. Thepresent embodiments are, therefore, to be considered in all respects asillustrative and not restrictive.

It should be understood that various changes and modifications to thepresently preferred embodiments described herein will be apparent tothose skilled in the art. Such changes and modifications can be madewithout departing from the spirit and scope of the present invention andwithout diminishing its intended advantages. It is therefore intendedthat such changes and modifications be covered by the appended claims.

1-38. (canceled) 39: A support assembly for an expansion joint strip,said assembly comprising: an elongate base strip including at least twolaterally spaced locating walls; a plurality of discrete support moduleseach being detachably connected to the locating walls at longitudinallyspaced positions along the base strip; and means for adjusting theheight of the expansion joint strip relative to at least one of thesupport modules. 40: The support assembly of claim 39 also comprising anexpansion joint strip cover adapted to support the expansion join stripand being arranged to be supported by one or more of the supportmodules. 41: The support assembly of claim 40 wherein each of themodules includes a U-shaped channel configured to cradle the expansionjoint strip cover. 42: The support assembly of claim 40 wherein theheight adjustment means includes a pin being designed to locate at oneof a plurality of different height positions relative to thecorresponding support module. 43: The support assembly of claim 42wherein the pin is received in one of a plurality of locating holes inthe support module, the strip cover being designed to rest on the pin tosupport the expansion joint strip at the required height. 44: Thesupport assembly of claim 43 wherein the pin is enlarged at one end forpress-fit engagement with said one of the locating holes. 45: Thesupport assembly of claim 39 wherein the locating walls are each in theform of stiffening ribs designed to strengthen the base strip. 46: Thesupport assembly of claim 45 wherein the support modules include a pairof spaced support legs each being perforated to promote the flow ofconcrete and encasing of said modules. 47: The support assembly of claim39 wherein said locating walls include a pair of outer locating wallsand a central locating wall. 48: The support assembly of claim 47wherein the base strip includes a groove or slot underlying the centralwall and designed to allow lateral movement of the strip. 49: Thesupport assembly of claim 39 also comprising another base strip joinedto said base strip at an expansion joint juncture. 50: A method ofinstalling an expansion joint strip in a concrete slab, said methodcomprising the steps of: providing an elongate base strip having atleast two laterally spaced locating walls; providing a plurality ofdiscrete support modules; fitting two or more of the support modules tothe locating walls of the base strip at spaced longitudinal positionsalong the base strip; placing the expansion joint strip upon one or moreof the modules and adjusting the height of said strip relative to atleast one of said modules; and pouring concrete to at least partly burythe base strip, the support modules and the expansion joint strip.